Amazing stuff!
"Their findings, published in the Monthly Notices of the Royal Astronomical Society, could offer valuable new insights into how galaxies formed in the early Universe.
Cosmic filaments are the largest known structures in the Universe: vast, thread-like formations of galaxies and dark matter that form a cosmic scaffolding. They also act as ‘highways’ along which matter and momentum flow into galaxies. Nearby filaments containing many galaxies spinning in the same direction – and where the whole structure appears to be rotating – are ideal systems to explore how galaxies gained the spin and gas they have today. They can also provide a way to test theories about how cosmic rotation builds up over tens of millions of light-years.
In the study ... found 14 nearby galaxies rich in hydrogen gas, arranged in a thin, stretched-out line about 5.5 million light-years long and 117,000 light-years wide.
This structure sits inside a much larger cosmic filament containing over 280 other galaxies, and is roughly 50 million light-years long. Many of these galaxies appear to be spinning in the same direction as the filament itself- far more than if the pattern of galaxy spins was random. This challenges current models and suggests that cosmic structures may influence galaxy rotation more strongly or for longer than previously thought.
The researchers found that the galaxies on either side of the filament's spine are moving in opposite directions, suggesting that the entire structure is rotating. Using models of filament dynamics, they inferred the rotation velocity of 110 km/s and estimated the radius of the filament’s dense central region at approximately 50 kiloparsecs (about 163,000 light-years).
“What makes this structure exceptional is not just its size, but the combination of spin alignment and rotational motion,” ...
The team used data from South Africa’s MeerKAT radio telescope, one of the world’s most powerful telescopes, comprising an array of 64 interlinked satellite dishes. This spinning filament was discovered using a deep survey of the sky called MIGHTEE, combined with optical observations from the Dark Energy Spectroscopic Instrument (DESI) and Sloan Digital Sky Survey (SDSS) to reveal a cosmic filament exhibiting both coherent galaxy spin alignment and bulk rotation."
From the abstract:
"Understanding the cold atomic hydrogen gas (H i) within cosmic filaments has the potential to pin down the relationship between the low density gas in the cosmic web and how the galaxies that lie within it grow using this material.
We report the discovery of a cosmic filament using 14 H i-selected galaxies that form a very thin elongated structure of 1.7 Mpc. These galaxies are embedded within a much larger cosmic web filament, traced by optical galaxies, that spans at least ~15 Mpc.
We find that the spin axes of the H i galaxies are significantly more strongly aligned with the cosmic web filament () than cosmological simulations predict, with the optically selected galaxies showing alignment to a lesser degree (). This structure demonstrates that within the cosmic filament, the angular momentum of galaxies is closely connected to the large-scale filamentary structure.
We also find strong evidence that the galaxies are orbiting around the spine of the filament, making this one of the largest rotating structures discovered thus far, and from which we can infer that there is transfer of angular momentum from the filament to the individual galaxies.
The abundance of H i galaxies along the filament and the low dynamical temperature of the galaxies within the filament indicates that this filament is at an early evolutionary stage where the imprint of cosmic matter flow on galaxies has been preserved over cosmic time."
Astronomers spot one of the largest spinning structures ever found in the Universe | University of Cambridge "Astronomers have identified one of the largest rotating structures ever reported: a “razor-thin” string of galaxies embedded in a giant spinning cosmic filament, 140 million light-years away."
Figure 2.Top left: the on-sky distribution of H i galaxies (squares), SDSS and DESI optical galaxies (circles and lines, depending on the availability of optical PA measurements), and the cosmic filament. The MIGHTEE COSMOS footprint is shown in a block. Other panels show the DESI multiband cutout image and the H i moment-1 map of each H i-selected galaxy. ...
